Study on the application and evaluation method of Zen aesthetic style in furniture design under the background of sustainability

Abstract

This study aims to explore the application of Zen aesthetics in contemporary furniture design within a sustainable context through rational data analysis, providing innovative insights and a reference framework for modern furniture design. First, grounded theory was employed to collect and evaluate design principles and elements through expert interviews, leading to the establishment of a hierarchical model. Next, the analytic hierarchy process was used to analyze and prioritize the elements of cultural and creative product design by calculating their weights. Finally, the fuzzy comprehensive evaluation method was applied for scheme selection and optimization. This study utilized Zen aesthetic-style tea table as a case study, the design was analyzed from the perspectives of aesthetic, functionality, emotionality and safety. The design scheme was optimized by incorporating Zen aesthetic principles, achieving an organic integration of Zen cultural elements with modern furniture design. The feasibility of this approach was validated through the design of a tea table. This comprehensive method addresses the gap in applying Zen aesthetics to modern furniture design, providing a scientific and systematic tool for the design and evaluation of contemporary furniture.

Introduction

As global environmental issues worsen and economic growth slows, people are increasingly living in a high-pressure, fast-paced environment. This fast-paced and restless lifestyle has become a daily norm for many individuals¹. However, this way of living not only lacks lasting satisfaction but also often leads to mental fatigue, exhaustion, and even psychological breakdowns². As a result, more and more people are seeking ways to achieve inner balance³. In response to this growing need for mental and emotional well-being, the role of furniture design has evolved beyond mere functionality. Most traditional furniture designs available today rely on standardized production processes, neglecting the deeper connection between products and consumers. This fast-food approach to furniture design often fails to satisfy people’s inner needs. Additionally, many modern furniture products lack environmental awareness⁴, leading to pollution and conflicting with the current pursuit of sustainable development.

In today’s fast-paced, high-pressure life, incorporating the Zen aesthetic style into product design has become a popular solution⁵. The Zen aesthetic style advocates for a return to simplicity, seeking inner peace and harmony in beauty⁶. It provides a sanctuary for mental tranquility^7,8, offering an environment that fosters wisdom through its minimalist and unadorned expression, making it one of the most significant aesthetic styles⁹. By deeply perceiving the beauty of nature, Zen aesthetics allows individuals to escape the clamor of reality¹⁰, helping them to achieve inner insight and serenity^11,12. Integrating Zen aesthetics into modern design undeniably positively impacts the spiritual and mental lives of contemporary society^13,14.

As environmental concerns become increasingly pressing, consumers are placing greater emphasis on product sustainability, viewing it as a key factor in ethical consumption¹⁵. In product design, sustainability is guided by the three core principles of “Reduce, Reuse, and Recycle”, collectively known as the 3R principles¹⁶. Within the context of sustainability, the 3R principles not only optimize resource utilization but also play a vital role in reducing environmental pollution and promoting eco-friendly production. These principles are deeply connected with Zen philosophy. First, Zen teaches the concept of “contentment in simplicity”¹⁷, emphasizing that true happiness does not stem from material accumulation but from inner fulfillment¹⁸. This aligns with the “Reduce” principle, which advocates minimizing resource dependence and eliminating unnecessary waste to create maximum value with minimal materials. In product design, the Zen aesthetic of “Minimalist Style” can inspire designers to create simple yet sophisticated works, reducing redundant materials and enhancing resource efficiency to align with sustainable development goals¹⁰. Second, a core Zen principle is “cherishing objects”¹⁹, which involves respecting the value of items and avoiding premature disposal. This concept resonates with the “Reuse” principle, which aims to extend product life cycles and prevent resource waste. In Zen culture, many items are reused; a notable example is the Japanese Zen practice of repairing broken objects using the “Kintsugi” technique²⁰, which enhances their beauty and renews their purpose. Such an attitude toward preservation is not only a form of practical wisdom but also a sign of respect for natural resources. In sustainable design, these Zen principles can guide product development, helping to extend product life spans and reduce resource consumption. Finally, Zen philosophy asserts that “all things are impermanent and in continuous cycles”²¹. Everything undergoes cycles of creation, decay, and renewal, a notion that is fundamentally aligned with the “Recycle” principle of sustainability. Nature itself operates as a cycle, and Zen awareness recognizes this ecological balance. Thus, in the context of sustainability, Zen aesthetics can inspire designers to select biodegradable and recyclable materials, ensuring that products can decompose naturally without leaving pollutants, thereby achieving harmony between humanity and nature.

In contemporary design research, numerous scholars have explored Zen aesthetics and examined how it inspires design creativity. Daisetsu Teitaro Suzuki, a Japanese scholar, first introduced Zen aesthetics and its application in Western design²². Steve Jobs, who was deeply influenced by Zen culture, applied these principles to Apple’s product design, reflecting the ideas of “Zen aesthetics” and “Less is More”²³. Many studies have since looked into integrating Zen elements into design^24,25, with Apple products being a key example. In furniture design, Yang et al. found that the concepts of “nature”, “simplicity”, and “harmony between man and object” in Zen aesthetics can enhance the artistic value of rattan furniture, meeting both the aesthetic and practical needs of modern people²⁶. Xiao Fei applied Zen aesthetics to the design of beds and sofas, using simple lines and forms to encapsulate complex shapes, emphasizing taste and elegance²⁷. Xiao et al. discussed how to integrate the essence of Zen culture into furniture design to elevate the spiritual and environmental value of the products²⁸. Li Yu, in his work Xianqing Ouji, summarized the style of ancient Chinese furniture craftsmanship, asserting that “simplicity is preferable to complexity, and naturalness is preferable to carving”, which aligns with the minimalist philosophy of Zen aesthetics²⁹. Zhou et al. found that contemporary new Chinese-style furniture design, while inheriting traditional Chinese culture, also incorporates the minimalist principles of Zen aesthetics³⁰.

Despite the existing applications of Zen aesthetics in furniture design, most current designs are limited to superficial visual presentations and formal pursuits³¹, overlooking their deeper impact on human spiritual needs and sustainable concepts. Furthermore, there are methodological shortcomings in current Zen aesthetic style research, which hinder designers from finding effective methods for designing and evaluating Zen aesthetic style products.

Based on these reasons, this study proposes a systematic design and evaluation method by integrating grounded theory (GT), analytic hierarchy process (AHP), and fuzzy comprehensive evaluation (FCE). It explores the application of Zen aesthetics in contemporary furniture design within the context of sustainability, using the table design as a case study. The design is evaluated from four aspects: aesthetics, functionality, emotional appeal, and safety. Ultimately, the study achieves the organic integration of Zen cultural elements into the table design, providing both theoretical foundations and practical references for furniture design with a Zen aesthetic style.

Materials and methods

Theoretical overview

Grounded theory

Grounded theory (GT) was initially introduced in the 1960s by sociologists Barney Glaser and Anselm Strauss in the field of sociology^22,24. The core concept of GT is to develop theories based on empirical data by inductively analyzing semi-structured interview materials and progressively refining them into systematic theories. This process allows for the abstraction of core concepts that reflect the essence of phenomena²⁵. For instance, Chao et al. used grounded theory to uncover potential design elements, providing valuable insights for the emotional design of smart products²³. Similarly, Wang et al. employed grounded theory to distill cultural elements from the World Cup and applied them to lamp design²⁶. Additionally, the GT method has been utilized across various design fields, including mechanical design²⁷, nursing ward design²⁸, and furniture design³².

Analytic hierarchy process

The analytic hierarchy process (AHP) is a decision-support method developed by American operations research expert Saaty³³. It is one of the most widely used multi-criteria decision-making tools³⁴. AHP combines the advantages of both qualitative and quantitative analysis and is extensively applied in decision problems across management, engineering, and economics³⁵. In this study, AHP is utilized during the design practice phase to prioritize furniture design elements, providing crucial reference indicators for the final product design. This method is widely used to determine the importance ranking of design elements. For example, Zhu et al. employed AHP to obtain priority rankings for design elements, significantly enhancing the rationality and user experience of surgical auxiliary equipment designs³⁶. Additionally, AHP has been broadly applied in various design fields, including lamp design³⁷, furniture design³⁸, aging product design³⁹, product form design⁴⁰, and sustainable design⁴¹. The specific steps are as follows:

Step 1 Constructing a hierarchical model. The decision problem is structured into a hierarchy with the goal at the top, criteria in the middle, and indexes at the bottom.

Step 2 Creating the judgment matrix. The evaluation indicators in the hierarchical model are compared in pairs to construct judgment matrix A.

1

In formula (1), n denotes the number of indicators, and represents the importance of factors i and j relative to the target, i, j = 1, 2, …, n.

Step 3 Calculate the indicator weights using the geometric mean method. Each indicator in the judgment matrix is multiplied row by row to obtain a new vector , as shown in formula (2).

2

In formula (2), n represents the order of the judgment matrix, and represents the elements within the judgment matrix.

Step 4 Calculate the geometric mean of each row of indicators in the judgment matrix, as shown in formula (3).

3

Step 5 Normalize the calculation results in the judgment matrix and determine the relative weight, as shown in formula (4).

4

Step 6 Consistency test. Calculate the maximum eigenvalue, as shown in formula (5).

5

Step 7 Calculate the consistency index CI, as shown in formula (6).

6

Step 8 Calculate the consistency ratio, as shown in formula (7).

7

In formula (7), RI represents the random consistency index, and the RI values for matrices of different orders are shown in Table 1. When CR < 0.1, the consistency test is considered acceptable; otherwise, the matrix needs to be adjusted and re-evaluated.

Table 1.

RI value of matrix order 1–9.

1	2	3	4	5	6	7	8	9
0	0	0.58	0.90	1.12	1.24	1.32	1.41	1.45

Fuzzy comprehensive evaluation

The fuzzy comprehensive evaluation (FCE) method was introduced by American control expert Zadeh⁴². FCE is a fuzzy synthesis evaluation process based on mathematical methods to quantify and score options, ultimately selecting the most optimal solution³⁹.

In the final decision-making stage, this study utilized the FCE method for option selection, leveraging the complementary strengths of AHP and FCE to enhance the scientific rigor and practical value of the analysis. This combined approach, validated in previous research, provides systematic support for complex, multidimensional decision-making processes^25,39,43. It is particularly well-suited for design and decision-making scenarios involving significant emotional factors, offering a more scientific and rational foundation for proposing effective solutions in product design.

The following process outlines the FCE model.

Step 1 Select evaluation parameters and establish evaluation criteria to form the evaluation factor set U. This is expressed as:

8

The evaluation criteria V set is the satisfaction rating criteria. This is expressed as:

9

Establish a set of weights A of different importance. This is expressed as:

10

11

Step 2 The single factor fuzzy evaluation set R_i is expressed as:

12

Thus, the single factor fuzzy evaluation set of each factor is as follows:

13

Based on the above single factor fuzzy evaluation set, the single factor fuzzy evaluation matrix R is expressed as:

14

Step 3 Based on the single factor fuzzy evaluation without interaction between evaluation factors and evaluation objects, the comprehensive evaluation set B is expressed as:

15

Design framework

The overall process is divided into three phases: obtaining design evaluation criteria, ranking the importance of design indicators, and designing and optimizing the solution.

Phase One: analysis of design evaluation criteria. Based on grounded theory, semi-structured interviews are conducted to establish the design evaluation standards for the Zen aesthetic style tea table.

Phase Two: hierarchical analysis. The analytic hierarchy process (AHP) is employed to build a hierarchical model and calculate the weights of the design indicators. Preliminary design solutions are developed according to the ranking of these indicators by importance.

Phase Three: screening and optimization of solutions. The fuzzy comprehensive evaluation (FCE) method is applied to screen and optimize the design solutions, thereby determining the most optimal final solution.

This design and development process is characterized by its scientific rigor and logical coherence. It moves beyond superficial, intuitive, and subjective design practices to a method that guides product development and design with strong correlations and logical structure, as shown in Fig. 1.

Fig. 1.

Design process framework.

Analysis and results

Grounded theory analysis

Selection of expert sample

The selection of experts is a critical step in ensuring the scientific rigor and credibility of the study. The qualifications and research fields of the experts serve as the primary criteria for determining their eligibility. In this study, 10 experts from diverse fields, including Zen masters, designers, university professors, and furniture business owners, were selected. The rationale for this sample size is as follows: First, in qualitative research, the sample size is not fixed but is determined by the point of data saturation—when no new information or themes emerge from the data⁴⁴. Previous studies suggest that a sample size of 10–30 participants is generally sufficient to achieve representativeness and data depth⁴⁵. Second, the choice of 10 experts strikes a balance between ensuring data richness and avoiding unnecessary complexity or redundancy that might arise from a larger sample. Additionally, the diversity of the experts—spanning Zen culture, design practice, academic research, and industry experience—ensures a comprehensive and multidimensional perspective, thereby enhancing the credibility of the qualitative data. This rigorous selection process allows the study to thoroughly capture the complex relationship between Zen aesthetics and tea table design, providing a robust empirical foundation for the research findings.

Zen masters excel at integrating Zen principles into everyday life, pursuing inner tranquility and wisdom. Interviewing Zen masters provides firsthand insights into the essence and core values of Zen aesthetics, offering information that literature reviews and theoretical research may not fully capture. This helps establish design guidelines and elements closely aligned with Zen aesthetics, avoiding superficial interpretations of Zen concepts. The rationale for conducting in-depth interviews with experienced designers is their expertise in innovative thinking and aesthetic expression, enabling them to create unique and captivating designs. Through these interviews, valuable insights and creative ideas can be gained on how to incorporate Zen aesthetic elements into cultural product design, which is crucial for enhancing the research’s innovation and practicality. University professors, known for their rigorous academic research and knowledge dissemination, ensure the accuracy and depth of the study’s content. Furniture industry business owners, with their keen insight into market trends and consumer preferences, ensure the commercial viability and sustainability of the design activities. The background data of the experts are shown in Fig. 2.

Fig. 2.

Background data of experts.

Data collection

To ensure comprehensive and objective responses, in-depth interviews were conducted with participants from different categories. During the interviews, the interviewer should avoid leading questions and instead guide the interviewees to express their own perspectives. With the interviewees’ consent, the interviews were recorded to ensure that the collected information is accurate and complete.

Purpose of Zen master interviews: To identifying Zen aesthetic features in Chinese cultural and creative products. The interview content was prepared in two parts, focusing on this objective. By interviewing Zen masters, the research aims to thoroughly explore the influence of Zen philosophy on contemporary Chinese furniture design, facilitating a better understanding and application of these elements in subsequent studies. The interview questions are presented in Table 2.

Table 2.

Outlines of interviews with Zen masters.

No.	Questions	Follow-up question
1	How do you define Zen aesthetics in your daily life and practice?
2	How do you integrate Zen aesthetics into your life? What impact does this have on you?	How does this affect you?
3	In modern society, does Zen aesthetics have a profound impact on people’s emotions and aesthetics? If so, can you give me some examples?	If so, can you give me some examples?
4	What role do you think Zen aesthetics plays in the inheritance and innovation of Chinese culture?
5	What are the points of convergence between sustainable design and Zen philosophy?
6	In your research or understanding, what are the key concepts and principles of Zen aesthetic style? How to apply these principles to modern cultural and creative product design?	How can these principles be applied to modern cultural and creative product design?
7	What changes do you think will occur in Zen aesthetics once it is applied to contemporary Chinese furniture design?
8	What suggestions do you have for designers engaged in cultural and creative product design on how to better balance traditional and modern elements in the design process?

Purpose of interviews with designers and university professors: The objective was to analyze the application of Zen aesthetics in the design of Chinese cultural products. Interviews with experienced designers aimed to thoroughly explore the practical implementation of Zen aesthetics in the design process. This analysis helps to better understand the value and significance of Zen aesthetics in the design field, providing inspiration and guidance for designers. The interview questions are listed in Table 3.

Table 3.

Outlines of interviews with designer and professors.

No.	Questions	Follow-up question
1	Do you have knowledge of Zen aesthetics?	If Yes, please talk about it。
2	How has Zen aesthetics influenced you personally and in your work?
3	In which design fields are Zen aesthetics commonly applied?
4	From your professional perspective, what unique aspects do Zen aesthetics bring to sustainable design?
5	Could you provide specific examples of how you have integrated sustainable design principles with elements of Zen aesthetics in your work?
6	How has Zen aesthetics inspired or guided you during the design process?	Has this changed your approach to design or your way of thinking?
7	Which principles and concepts of Zen aesthetics do you apply when designing the form of a product?	Do you have a picture that you can show me?
8	Which principles and concepts of Zen aesthetics do you apply when designing the color of a product?	Do you have a picture that you can show me?
9	Which principles and concepts of Zen aesthetics do you apply when designing the texture of a product?	Do you have a picture that you can show me?
10	Which principles and concepts of Zen aesthetics do you apply when designing the usability of a product?
11	Which principles and concepts of Zen aesthetics do you apply when designing the ambiance or mood of a product?

Purpose of interviews with business owners: The goal was to gain insights into market trends and consumer demands. As front-line observers of the market, business owners can provide direct information about consumer needs and market trends. Their unique perspectives on how to skillfully integrate Zen culture with furniture design are invaluable for creating Zen-inspired furniture that meets market demands while embodying deep cultural significance. The interview questions are listed in Table 4.

Table 4.

Outlines of interviews with business owners.

No.	Questions	Follow-up question
1	What do you consider the overall trends in the current furniture market?	What important changes or emerging trends do you foresee in the next few years?
2	How do you understand the relationship between Zen aesthetics and sustainable design?
3	What impact does the concept of sustainable design have on contemporary furniture design?
4	Which elements or spiritual connotations of Zen culture are most suitable for incorporation into furniture design?
5	What factors do you think consumers value the most?
6	What do you believe is key to maintaining a company’s competitiveness in the market?
7	What specific strategic plans or measures does your company have to address potential future market opportunities and challenges?

Open coding

Recorded interviews were transcribed and analyzed using ATLAS for Mac. To minimize subjectivity, open coding was employed to categorize raw data, identifying new insights from phenomena observed in the data. This process involved conceptualizing raw information, summarizing repeatedly to remove redundant and irrelevant data, ultimately resulting in 11 categories, as detailed in Table 5.

Table 5.

Open decoding process.

Original data representative sentence	Initial concept	Category
Minimalism does not equate to monotony. While simplicity is pursued, innovation should also be embraced. Eliminating unnecessary elements, the shape of the tea table should break away from conventional designs	Design integration of simplicity and innovation: The design is both simple and innovative, featuring a unique shape that stands out	Minimalist style
When selecting a tea table, I consider its ability to hold daily essentials such as books, beverages, or decorative items	Core functions of the table: The design addresses essential functions such as load-bearing capacity, stability, and user-friendliness	Practicality
Every grain of wood on the table tells a story of nature, offering me a brief escape from the hustle and bustle of city life. Its design transports my thoughts to a serene forest. Whenever I touch the surface of the table, the rustic feel of nature provides profound comfort to my soul	Connection with nature: The design enhances users’ connection with nature, fostering a sense of closeness to the natural world	Connect with nature
As time passes, this tea table reveals more stories, with wear and tear becoming cherished memories. This is precisely what I value	Durability and resistance to wear: The product is designed for longevity, with the ability to withstand daily wear and tear	Durability
The design is not only suitable for home environments but also considers various settings such as offices and study space	Versatility of application: The product is suitable for various settings and purposes	Easy to maintain
The selected materials should be not only aesthetically pleasing and durable but also environmentally friendly and compliant with health standards	Sustainable material use: The design prioritizes materials that are sustainably sourced and have minimal environmental impact	Environmentally materials
Whenever I sit by this Zen aesthetic tea table, the noise and tension within me seem to be quietly swept away by an invisible force, leaving behind only tranquility and inner peace. This is not just a piece of furniture; it is a space where I can reconnect with myself	Psychological impact on users: The design evokes feelings of tranquility and peace	Inspire reflection
The curves of the product remind me of flowing water outdoors, bringing a sense of nature into my living space. In designing the product, I drew inspiration from the contours of hills, aiming to incorporate the fluid forms of nature into daily life. Good design follows the laws of nature, without forced symmetry or excessive artificial embellishments; each angle is naturally formed	Harmony with natural forms: The design harmoniously blends with natural shapes and forms	Harmonious shape
The product must ensure that every joint is robust enough to withstand the pressures of daily use. Even with children or pets in the house, there is no need to worry about it toppling easily	Structural stability: The product is built with solid construction, ensuring stability	Sturdy structure
The wood grain is clearly visible, creating the feeling of directly touching nature. I prefer using natural stone rather than artificial materials, as their texture and color subtly change with light and viewing angles, providing a sense of natural beauty	Natural material authenticity: The use of minimally processed materials retains their natural texture and feel, emphasizing both tactile and visual authenticity	Original texture
Low-saturation colors reflect tranquility and restraint, with the products palette echoing the beauty of nature while avoiding overly striking colors. The combination of deep brown and gray tones is simple yet profound, evoking the image of trees and rocks in a forest	Color choices reflecting nature: The design incorporates natural and understated colors	Plain color application
Sitting in front of the tea table, I often find myself slipping into contemplation. It seems to remind me that the essence of life is not in the pursuit of flawless perfection but in appreciating and accepting the natural and authentic moments	Elements promoting reflection: The design includes elements or forms that encourage users to reflect and think deeply	Cultural connotation

Axial coding

Axial coding involved organizing raw data into related categories and identifying major categories based on logical relationships. The process distilled data into three main categories: functionality, human–machine interaction, and safety, as shown in Table 6.

Table 6.

Axial coding process.

Main category	Subcategory	Connotation
Aesthetics	Minimalist style	On the basis of maintaining simple aesthetics, seek innovation in design. Use concise expressions to find deep beauty and meaning
	Harmonious shape	Emphasize the harmonious integration of form and nature in tea table design
	Original texture	Pay attention to the natural texture and texture of the tea table material itself, and increase the richness of vision and touch
	Plain color application	Use natural and simple colors to reflect the pursuit of natural beauty
Functionality	Easy to maintain	In addition to being a tea table, whether it has functions suitable for the applicable space
	Durability	The selection of tea table materials and structures should ensure durability for long-term use
	Practicality	The basic functions of the tea table, including stability, sufficient surface space, etc
Emotionality	Inspire reflection	Whether the tea table design can provide users with a quiet or calm experience
	Inspire reflection	Whether the tea table design can trigger users’ thinking about life attitudes and aesthetic concepts
	Connect with nature	Whether the tea table design can help users feel connected to nature and promote inner peace
Safety	Environmentally materials	Choose natural materials to reduce environmental pollution caused by excessive design
	Sturdy structure	Extend the service life through solid structural design. Reduce the damage that may be caused by sharp corners

Selective coding

Selective coding extracted the most critical core categories by analyzing the relationships between major categories and integrating them into a coherent framework. This method provided a comprehensive summary of category interrelations, as detailed in Table 7.

Table 7.

Selective coding process.

Typical path relationships	Nature of relationship	Connotations
Aesthetics → User satisfaction → Design solution	Intermediary relationship	Whether the aesthetics is reflected will affect user satisfaction and thus affect the design plan
Functionality → User satisfaction → Design solution	Intermediary relationship	Whether the functionality is reflected will affect user satisfaction and thus affect the design plan
Emotionality → User satisfaction → Design solution	Intermediary relationship	Whether emotionality interaction will affect user satisfaction and thus affect the design plan
Safety → User satisfaction → Design solution	Intermediary relationship	Whether the safety is reliable will affect user satisfaction and thus affect the design plan

Theoretical saturation testing

Theoretical saturation testing ensured the validity and reliability of the research model. By re-analyzing three reserved data sets until no new concepts or categories emerged, we confirmed the theoretical saturation of the model.

Hierarchical model construction

Using expert interviews and the analytic hierarchy process (AHP), we organized and categorized user requirements for product into three levels: target layer, criteria layer, and indicator layer. The target layer represents the overall user demand for Zen aesthetic style tea table (V). The criteria layer divides user requirements into Aesthetics (A1), Functionality (A2), Emotionality (A3), and Safety (A4). The indicator layer further breaks down these criteria into specific needs, as shown in Fig. 3. This hierarchical model sets the stage for subsequent matrix analysis.

Fig. 3.

Product design hierarchy model.

User demand analysis based on AHP

Calculating user requirement weights

After building the product design hierarchical model, the AHP hierarchical analysis method is used to construct the user demand judgment matrix. Complex problems under multi-objective conditions can be analyzed in a hierarchical manner, and then the decision evaluation consistency can be verified to further determine the weight of user needs, so as to reduce decision-making deviations. The calculation steps are as follows. The calculation steps are as follows:

Step 1 Construct the judgment matrix. First, invite the above 10 experts to compare the design indicators of Zen aesthetic table in pairs to construct the judgment matrix. Use the 1–9 scaling method in Table 8 to assign values.

Table 8.

Judgment matrix index importance level numerical scale table.

Scale value	Importance level	The meaning of importance level
1	Equally important	Indicator X is of equal importance compared to indicator Y
3	Slightly important	Indicator X is marginally important compared to Indicator Y
5	Outstandingly important	Indicator X is significantly more important than Indicator Y
7	Extremely important	Indicator X is extremely important compared to indicator Y
9	Completely important	Indicator X is completely important compared to Indicator Y
2, 4, 6, 8	Eclectic use	The importance level is between two adjacent importance levels
1/2, 1/3 … 1/9	Anti-comparison	If the importance scale value of indicator X over indicator Y is n, and vice versa is 1/n

Step 2 Calculate the user demand weight values using formulas (2)–(4), as shown in Tables 9, 10, 11, 12 and 13.

Table 9.

Judgment matrix and weights of each indicator requirement (A–D) at the target layer.

V	A	B	C	D	W
A	1	2.857	2.803	4.225	0.4695
B	0.350	1	1.200	3.530	0.0855
C	0.357	0.833	1	1.395	0.2938
D	0.237	0.283	0.717	1	0.1512

Table 10.

Aesthetics indicator requirements (A₁–A₄) judgment matrix and weights.

A	A1	A2	A3	A4	W1
A1	1	2.857	2.803	4.225	0.4988
A2	0.350	1	1.200	3.530	0.2347
A3	0.357	0.833	1	1.395	0.1658
A4	0.237	0.283	0.717	1	0.1006

Table 11.

Functional indicator requirements (B₁–B₃) judgment matrix and weights.

B	B1	B2	B3	W2
B1	1	0.179	0.263	0.0918
B2	5.600	1	3.093	0.6381
B3	3.800	0.323	1	0.2701

Table 12.

Emotionality indicator requirements (C₁–C₃) judgment matrix and weights.

C	C1	C2	C3	W3
C1	1	0.385	0.417	0.1668
C2	2.600	1	0.714	0.3759
C3	2.400	1.400	1	0.4574

Table 13.

Safety indicator requirements (D₁–D₂) judgment matrix and weights.

D	D1	D2	W4
D1	1	0.526	0.3448
D2	1.900	1	0.6552

Step 3 Perform a one-time test using formulas (5)–(7). The test results are shown in Table 14. The CR index is less than 0.1, which meets the consistency test.

Table 14.

Consistency test results.

	V	A	B	C	D
CI	0.005	0.029	0.031	0.010	0
RI	0.890	0.890	0.520	0.520	0
CR	0.006	0.033	0.060	0.019	Null

Design indicator ranking

After the consistency test of each factor is passed, the weight values of each item in the user demand criteria layer of Zen aesthetic style tea table are multiplied by the weight values of the corresponding indicator layer, and the comprehensive weight value of each demand indicator in the entire target demand system can be calculated. Sort the results by weight. As shown Table 15.

Table 15.

Comprehensive weight of each demand.

Target layer	Criteria layer W	Indicator layer W1–W2		Comprehensive weight	Target layer
V	Aesthetics W1 = 0.4695	A1	0.4988	0.2342	1
		A2	0.2347	0.1102	4
		A3	0.1658	0.0778	6
		A4	0.1006	0.0472	10
	Functional W2 = 0.0855	B1	0.0918	0.0078	12
		B2	0.6381	0.0546	7
		B3	0.2701	0.0231	11
	Emotional W3 = 0.2938	C1	0.1668	0.0490	9
		C2	0.3759	0.1104	3
		C3	0.4574	0.1344	2
	Safety W4 = 0.1512	D1	0.3448	0.0521	8
		D2	0.6552	0.0991	5

Based on the calculation results, the importance of criteria in Zen aesthetic tea table design, ranked from most to least significant, are as follows: Aesthetic criteria, Emotional criteria, Safety criteria, and Functional criteria. In the design process of the tea table in this study, the connection between Zen aesthetic principles and sustainable design is profoundly reflected through the four dimensions in the aforementioned hierarchical model.

In the design process of the tea table in this study, the connection between Zen aesthetic principles and sustainable design is profoundly reflected through the four dimensions of Aesthetic, Functionality, Emotionality, and Safety in the aforementioned hierarchical model.

Firstly, in the aesthetic (A) dimension, the design adopts a minimalist style (A1) and harmonious shape (A2), avoiding excessive decoration and pursuing simplicity in shape and visual balance, embodying the Zen principle of ‘less is more’. Simultaneously, the preservation of the material’s original texture (A3) and the application of plain colors (A4) showcase the beauty of nature, resonating with the Zen aesthetic’s reverence for simplicity and authenticity. This minimalist design not only reduces material waste but also directly reflects the core principles of sustainable design through the use of natural materials such as wood and stone. In this study, the tabletop is crafted from black walnut wood, a natural and environmentally material (D1). Its unique growth patterns and warm texture not only imbue the tea table with cultural connotation depth (C3) but also demonstrate the Zen aesthetic’s respect for natural resources and a lifestyle of simplicity through the material’s recyclability.

In the functionality (B) dimension, the design emphasizes ease of maintenance (B1) and durability (B2), ensuring that the tea table remains in excellent condition during daily use, thereby reducing maintenance costs and resource consumption. Practicality (B3) considerations ensure that the tea table is not only aesthetically pleasing but also meets users’ practical needs, such as providing ample storage space or adapting to various usage scenarios.

In the emotionality layer (C), it ranks second in the criteria layer in terms of concentrated weight. The design emphasizes the use of natural materials and nature-inspired forms to evoke user reflection (C1) and foster a connection with nature (C2), conveying Zen aesthetics’ philosophy of respect for and harmonious coexistence with nature. The integration of cultural connotation (C3) not only adds spiritual depth to the design but also, through the key element of “establishing a connection with nature” (C2), fulfills modern consumers’ desire to return to nature, imbuing the product with deeper emotional value. This design not only strengthens the spiritual essence of Zen aesthetics but also enhances the user experience through emotionality, transforming the tea table into a bridge connecting nature, culture, and the human spirit.

Finally, in the safety (D) dimension, the design ensures user safety by selecting environmentally materials (D1) and ensuring a sturdy structure (D2). The durability (B2) and practicality (B3) of the design extend the product’s lifecycle, reducing resource waste. In this study, the supporting structure of the tea table is made of unpolished natural stone, connected to the tabletop using mortise and tenon joints. The robust and durable nature of the stone further enhances the safety of the tea table, while the rough texture of the stone contrasts with the smooth tabletop, enhancing the aesthetic appeal. The use of sturdy natural materials extends the product’s lifespan, reducing the need for frequent replacements and resource waste, thereby reinforcing the product’s sustainability.

These principles seamlessly integrate the spiritual essence of Zen aesthetics with sustainable principles, creating a tea table that combines functionality and cultural depth, offering users a dual experience of visual and spiritual enjoyment. This embodies the unity of sustainable design and Zen aesthetics. These design principles will provide important guidance for subsequent product design.

Design practice

Design concept

According to the ranking results of the above-mentioned Zen aesthetic tea table design standards, we selected the first six indicators with greater weights to conceive the scheme, as shown in Table 16.

Table 16.

Design concept.

Design indicators	Design concept
Minimalist style (A1)	The design emphasizes clean and simple lines, eliminating all unnecessary decoration and complexity. The goal is to reduce the product to its most essential form while maintaining a focus on innovation and uniqueness
Connection with nature (C2)	Design elements are drawn from natural features such as mountains, rivers, and trees, using smooth and gentle lines. Soft and elegant colors evoke images of the natural landscape
Inspire reflection (C1)	The design is shaped to carry metaphorical and symbolic meanings, with colors that naturally contrast to evoke introspective emotions. The textures, whether smooth or rough, invite deep thought and reflection through tactile experience
Harmonious shape (A2)	Soft strokes outline the shape of the tea table, prioritizing the harmony of the overall form over intricate details
Sturdy structure (D2)	The design must consider factors such as load-bearing capacity, stability, and structural integrity to ensure the product does not collapse, break, or present other safety hazards during use
Original texture (A3)	Natural materials are selected to emphasize the purity and authenticity of these materials. The natural textures and patterns are preserved to convey a simple and natural ambiance

Design solution expression

According to the design indicators, the design scheme is sketched.

Design scheme 1

This design features a tabletop made from decayed wood, imbuing the product with a sense of time and history. The natural shape of the decayed wood itself contributes to this ritualistic aesthetic. Two symmetrical stone slabs are horizontally placed on the ground to support the tabletop, enhancing the design’s visual and tactile richness. As illustrated in Fig. 4.

Fig. 4.

Design scheme 1.

Design scheme 2

This scheme combines wood and stone to create a simple and refined design. The tabletop is made from a branched tree trunk, while naturally shaped stones are used as supports. This choice of materials emphasizes not only the pursuit of natural beauty but also the durability and stability inherent in stone. The use of stone and wood symbolizes the Zen aesthetic of nature, where stone represents mountains and wood represents forests, embodying a harmonious coexistence. As illustrated in Fig. 5.

Fig. 5.

Design scheme 2.

Design scheme 3

This design features a marble base paired with an unprocessed weathered wooden tabletop, creating a textural contrast that highlights the simplicity and natural beauty. As illustrated in Fig. 6.

Fig. 6.

Design scheme 3.

Fuzzy comprehensive evaluation

The fuzzy comprehensive evaluation method is a comprehensive evaluation approach based on fuzzy mathematics (1) This method is characterized by clear results and strong systematicity, effectively addressing the problem of unquantifiable subjective factors introduced by designers, thereby helping designers select the optimal solution (2) The specific steps are as follows:

Step 1 Invite 10 experts to participate in the evaluation of the criteria indicators. The criteria are denoted as U = {u1, u2, u3, u4}, representing the aesthetics criterion, functionality criterion, emotionality criterion, and safety criterion.

Step 2 Establish evaluation levels and scoring standards. Define the evaluation set V = {V1, V2, V3, V4} = {Very Satisfied, Satisfied, Average, Dissatisfied} with corresponding scores of 90, 80, 70, and 60, respectively.

Step 3 Construct the fuzzy comprehensive evaluation matrix. Invite evaluators to use the design evaluation model to assess the three preliminary schemes. The evaluators’ scores for each sub-criterion at each evaluation level are tallied to obtain the membership degree of each evaluation indicator relative to each evaluation level, thereby constructing the fuzzy comprehensive evaluation matrix R for each design scheme.

Taking Scheme 2, which received the highest score, as an example, R_A represents the evaluation matrix for the aesthetics criterion in Scheme 2; R_A represents the evaluation matrix for the functionality criterion in Scheme 2; R_A represents the evaluation matrix for the emotionality criterion in Scheme 2; R_A represents the evaluation matrix for the safety criterion in Scheme 2. The evaluation matrix is as follows:

Step 4 Perform a synthetic operation on the weight of each evaluation indicator and the corresponding evaluation matrix R to calculate the evaluation weight vector P of each indicator at the product solution standard layer. From Tables 8, 9, 10, 11 and 12, we can see that the weight vector of each indicator is:

According to the weight calculation, the evaluation weight vector P of each indicator in the scheme criteria layer can be obtained as follows:

On this basis, the fuzzy comprehensive evaluation matrix of the overall indicators can be constructed:

Then the comprehensive evaluation vector of the table design is:

Finally, through the weighted calculation of the comprehensive evaluation vector S and the corresponding scores of the comment set levels, Scheme 2 achieves a total percentage evaluation score of 81.85, while Scheme 1 and Scheme 3 receive scores of 73.93 and 75.34. The detailed calculation process for Scheme 1 and Scheme 3 is provided in Appendix S1. Based on the FCE analysis results, Scheme 2, which obtained the highest score, is ultimately selected for further in-depth design and processing.

Results

Program evaluation and improvement

In the fuzzy comprehensive evaluation of Scheme 2, although it achieved the highest overall score, the scores for Harmonious Shape (A2), Ease of Maintenance (B1), and Sturdy Structure (D2) in its indicator layer were slightly lower than other criteria, as shown in Fig. 7. To ensure the final product excels in these aspects, targeted adjustments were made to each of these three points.

Fig. 7.

The results of membership degree.

To enhance the harmonious shape (A2) of the table, the table abandons rigid design conventions and adopts an asymmetrical form, presenting a natural and harmonious aesthetic. At the same time, its smooth lines and meticulously hand-polished rounded edges create a sense of intimacy between the user and the table, allowing people to experience the feeling of harmony between humans and nature while using it.

To improve the product’s ease of maintenance (B1), a modular design is adopted. The plug-and-play connection structure allows users to easily assemble and disassemble the product without relying on specialized tools. Additionally, to facilitate transportation, the product’s dimensions have been carefully optimized—while ensuring compliance with fundamental ergonomic principles—to minimize space occupation during transport and storage.

To enhance the sturdy structure (D2) of the tea table, a special structural design was implemented. A hole was drilled at one end of the tabletop, allowing a stone insert to be securely fixed in place, seamlessly integrating the wooden surface with the stone support structure. This design not only ensures structural stability and safety but also conveys a sense of natural beauty.

The revised Scheme 2 is illustrated in Fig. 8.

Fig. 8.

Sketch of the scheme improvement.

The final form of the product eliminates all unnecessary decorations, featuring a design with clean and simple lines to achieve an ultra-minimalist aesthetic. Additionally, the cross-section adopts a “Y”-shaped tree trunk structure, preserving natural elements and fostering a closer connection between the user and nature. The final dimensional representation of the product is shown in Fig. 9.

Fig. 9.

Final product design drawings.

To better illustrate the design style and details of the product, the physical prototype was photographed to capture its design style and details. The captured images were then processed using Adobe Photoshop for Mac to enhance lighting and shadow effects, ensuring an accurate representation of the product’s aesthetic and functional attributes. Please refer to Appendix S2 for details on the product processing and manufacturing procedures. The final product rendering is shown in Fig. 10.

Fig. 10.

The final product rendering.

Product design factor analysis

Based on the weight analysis of the Zen aesthetic style tea table indicators, as shown in Fig. 11, this study evaluates the weight values of each layer of indicators for the Zen aesthetic style tea table. The design analysis is summarized as follows:

Fig. 11.

Schematic diagram of design indicator weights.

In the criteria layer, aesthetics has the most significant impact on the Zen aesthetic style tea table, indicating that the foundation of aesthetic perception lies in the explicit design features, such as form, color, and materials. Within the Aesthetics level (A), the Minimalist style (A1) emerges as the most crucial design element, which aligns with previous studies advocating minimalist design in Zen aesthetics⁴⁶. Conversely, functionality has the least influence on the Zen aesthetic style tea table, reflecting that as living standards rise, contemporary consumers’ demands for furniture are gradually shifting from traditional functionality to deeper spiritual and aesthetic pursuits⁴³.

The enotionality also significantly impact the Zen aesthetic style tea table. In this layer, “Connecting with Nature” (C2) and “Cultural Connotation” (C3) scored relatively high. In the fast-paced modern lifestyle, people desire to establish a connection with nature through their home environment to alleviate stress and achieve inner peace. “Connecting with Nature” resonates with consumers’ yearning to return to nature, fulfilling their desire for natural experiences and spiritual comfort⁴⁷. “Cultural Connotation” meets consumers’ pursuit of cultural identity and deeper spiritual values⁴⁸. This cultural connotation endows the product with greater value⁴⁹, making it not just a piece of furniture but also a vehicle for conveying culture and spirit.

In the safety criterion, “Environmentally materials” (D1) and “Study structural” (D2) are the most fundamental requirements in furniture design. In contemporary furniture products, sustainable design emphasizes the environmental friendliness and renewability of materials⁵⁰. By selecting harmless and biodegradable materials, designers can minimize environmental impact while ensuring user safety during furniture use. Furthermore, rational structural design can extend the product’s lifespan, reduce resource waste⁵¹, and meet the expectations of modern consumers for eco-friendly products.

The impact of the Functionality layer on Zen aesthetic tea table design is relatively minor, indicating that as living standards improve, contemporary consumers are shifting their preferences from traditional functional needs toward deeper spiritual and aesthetic pursuits. Despite its lesser influence, Functionality remains an indispensable aspect of Zen aesthetic tea table design. By balancing Functionality with other criteria, the product can not only meet users’ practical needs but also achieve a harmonious integration of functionality and cultural significance.

Discussion

This study integrates grounded theory (GT), analytic hierarchy process (AHP), and fuzzy comprehensive evaluation (FCE) to explore the application and evaluation methods of incorporating Zen aesthetics into furniture design within the sustainability context. This research clarifies the application of Zen aesthetic principles in tea table design, enhancing the aesthetic value of products and improving the lack of cultural depth in Chinese tea table design. Meanwhile, by integrating Zen aesthetics with the 3R principles of sustainability, this approach not only enhances the cultural and aesthetic value of the product but also fosters a deep reverence for the natural environment. This integration encourages encourages individuals to adopt a simple and humble way of living, reducing excessive material desires in today’s fast-paced and chaotic world, ultimately achieving inner peace and tranquility.

While this study has achieved certain results, it also has limitations. Firstly, the proposed methodology has been primarily applied to tea table design, limiting its scope of applicability. Its effectiveness in other furniture categories has yet to be validated. Secondly, Zen aesthetics is a profound and expansive philosophical system. Due to the limitations of time and sample size, this study has only captured a partial understanding through literature review and interviews, making it difficult to present its full depth comprehensively. Thirdly, although the experts consulted in this study have extensive industry experience, it is important to note that subjective judgment is inevitable in the expert evaluation process using the analytic hierarchy process (AHP). Additionally, the relatively small sample size of experts in this study may affect the generalizability of the results. Fourthly, this study does not systematically assess users’ cultural backgrounds or designers’ familiarity with Zen aesthetics, which may lead to variations in interpreting design elements such as form, color, and materials when translating abstract Zen aesthetics into tangible product features.

Regarding the above limitations, future research could focus on the following areas for improvement and expansion. Firstly, this method will be applied to a broader range of furniture products to further verify its applicability. Secondly, future research will continue to expand the scope of literature review and increase the sample size of Zen aesthetics experts to obtain a more comprehensive and in-depth understanding of Zen aesthetics. Thirdly, the sample size of experts will be increased to reduce biases caused by individual subjectivity. Additionally, future research will incorporate users and designers from diverse cultural backgrounds to explore the adaptability of Zen aesthetics in different cultural contexts and optimize its expression in product design.

Surprisingly, this study also discovered a potential connection between Eastern Zen aesthetics and Western Scandinavian design. Although these two design styles originate from different cultural backgrounds, they share similar design philosophies and aesthetic features in many ways. For instance, Scandinavian design emphasizes simplicity, natural materials, and neutral colors, which closely align with the characteristics of Zen aesthetics. This similarity warrants further exploration in future design research.

Conclusions

From a methodological perspective, this study integrates Grounded Theory, the analytic hierarchy process (AHP), and fuzzy comprehensive evaluation (FCE) to construct a design methodology for Zen aesthetic tea tables. On one hand, this approach helps quantify the otherwise abstract Zen aesthetic style, providing designers with a scientific and systematic tool to more efficiently design and evaluate tea tables that embody Zen aesthetics. On the other hand, it effectively mitigates issues arising from designers’ subjective interpretations of Zen aesthetics, such as superficial cultural connotations and low-quality design outcomes. The research findings reveal that the dimensions influencing Zen aesthetic tea table design include four criteria layers: aesthetics (A1), functionality (A2), emotionality (A3), and safety (A4). Among the indicator layers under these criteria, minimalist style (A1), connection with nature (C2), inspire reflection (C1), harmonious shape (A2), sturdy structure (D2), and original texture (A3) have relatively higher comprehensive weights, while “easy to maintain (B1)” and “practicality (B3)” have relatively lower comprehensive weights. The results indicate that future Zen aesthetic tea table designs should prioritize user emotional needs, placing greater emphasis on Aesthetics and Emotionality to meet people’s yearning for natural experiences and spiritual solace in today’s fast-paced lifestyle. These findings provide valuable guidance for the innovative design of Zen aesthetic tea tables, contributing to enhanced user experiences.

From a philosophical perspective, in the context of sustainable design for Zen aesthetic tea tables, Zen aesthetics advocates for the “minimalist style” as a reflection of simplicity and the “connection with nature” and “original texture” as expressions of a naturalistic worldview. These principles provide a foundational value base for tea table design within a sustainable framework. Extending from this, the design philosophy rejects redundant and extravagant ornamentation, emphasizing instead the use of clean forms and the preservation of natural materials to align with the 3R principles of sustainability. From an emotional perspective, Zen aesthetics employs “harmonious shape” to redefine the relationship between users and products, evoking “inspire reflection” in users. When designs imbue objects with reflective emotional qualities, they embody the Zen aesthetic value of “cherishing objects” (惜物). As a result, consumers no longer view products as disposable items subject to rapid obsolescence but instead, through “Sturdy Structure”, extend the product’s lifecycle, indirectly mitigating the environmental pressures caused by planned obsolescence. Ultimately, Zen aesthetic style in furniture design under the background of sustainability is not merely a product with an aesthetic style but a medium that evokes emotional experiences, awakening a reverence for nature and a reflection on personal desires.

Author contributions

T.W.; methodology: T.W. and Y.Z.; software: T.W.; supervision: B. H.;validation: T.W., Y.Z., L.Z., Y.X. and L.L.L.P.; formal analysis: T.W. and Y.Z.; investigation: T.W., Y.Z. and L.Z.; resources: T.W.; data curation: T.W. and L.Z.; Writing—original draft: T.W.; Writing—review and editing: T.W. and Y.Z.; visualization: T.W. and Y.X.; supervision: T.W.; project administration: T.W.; funding acquisition: T.W. All authors have read and agreed to the published version of the manuscript. All authors reviewed the manuscript. All authors listed have made substantial, direct and intellectual contribution to the work, and approved it for publication.

Data availability

Data is provided within the manuscript or supplementary information files.

Declarations

Competing interests

The authors declare no competing interests.

Ethical Statement

This study primarily focuses on methodological research. Since it did not involve any invasive procedures, clinical trials, or anatomical studies involving humans or animals, ethical approval was deemed unnecessary. The Ethical Committee of Anyang Institute of Technology granted an exemption from ethical review, confirming that the study adhered to ethical standards and guidelines.

Supplementary Information

The online version contains supplementary material available at 10.1038/s41598-025-93860-2.