TRIZ (Theory of Inventive Problem Solving) classifies inventions into five novelty levels (For example see ). At level 1 are slight modifications of the existing systems. Typically they are localized within a single sub-‐system. At level 2 are those inventions that resolve a system conflict or contradiction (called a technical contradiction between two parameters of a system), using usually inventive solution or inventive principle used to solve similar problems in other systems. This is what resulted in the most used TRIZ tool of contradiction matrix and 40 inventive principles. In fact, since 77% of inventions were at level 1 or level 2, TRIZ in popular press and by many consultants/trainers have been reduced to exploring and explaining contradiction matrix and 40 inventive principles. However, it is the deeper understanding that leads to level 3 and above inventions where TRIZ can be very powerful. At level 3, the inventions change one subsystem or resolve the system conflicts in a fundamental way.
TRIZ found that about 19% inventions were at level 3. At level 4, the invention gives birth to new systems using interdisciplinary approaches. Less than 4% inventions were found to be at this level. The level 5 inventions are closer to a recently discovered scientific phenomenon. They start a new engineering discipline and have long range impact on the technological development of human race. For example,  considers, agriculture, money, hammer, wheel, pump, lasers, etc as level 5 inventions. Altshuller has also conjectured through the s-‐curve correlation with the levels of inventions to map the level of invention at various stages of evolution of a technology. As per these S-‐curves, a new domain typically starts with a level 5 invention which is closer to a scientific discovery. In turn, the initial invention give rise to level 4 inventions which may give lower level inventions as people start solving the problems to convert the initial invention into a working system for use in real life. It so happens at this point of time in the evolution of a technical system that a higher level invention suddenly springs up and creates the rapid value and expansion of the technology across the world. This phase corresponds to the steep rise of the technology’s value on its S-‐curve. The levels of inventions after this second peak start going downwards and people keep on solving lower level problems till the end of life of the technology when it is replaced by new technology. Our aim in this paper is to use the levels of invention and timing information as described in TRIZ and give heuristics to quantify the level of an invention and to give an informed guesstimate on probable life of an invention in terms of number of years. These heuristics have been worked out by the author using TRIZ for more than a decade in analyzing patents and estimating the level of inventions using the heuristics. We also have made a spreadsheet based tool that uses these heuristics and quantifies the level of invention and also gives life of the patent/invention. 2. Quantification of levels of inventions Key conceptual construct of TRIZ is a system – specifically a technical system. A set of elements that interact together to perform a function defines a system. The function is modeled as an interaction of two substances and a field – substances and fields are defined in TRIZ in very broad terms. The function to be performed or delivered identifies the system. In fact, most of the systems are developed based on what can be called the operating principles to deliver a function. For example, if you look at the function -‐ cleaning teeth – the tooth brush or its variants are developed on the operating principle of friction to clean teeth. One can develop entirely new range of systems, hence products and services if one changes the operating principle. For example, if instead of friction we use ultrasound waves to clean teeth, we may have entirely new product or capability to clean teeth. An invention is always studied and evaluated in comparison to the existing method, mechanism, system, problem, or, operating principle of delivering a function. Further, every system exists in an environment of super-‐systems, alternate systems, and even anti-‐systems. Also, the elements that constitute a system may themselves be considered as a set of elements delivering a function – such sets are called sub-‐ systems if they deliver a function that aids or contributes to the main or secondary functions delivered by the system as a whole. Hence, we have a hierarchy of systems – Subsystems, System and Super-‐system. 2.1 Invention is some change in the System Hierarchy In an invention, we typically see some change in the subsystem, system or super-‐system. Figure below gives typical changes at the abstract level that can be defined at the subsystem, system and super-‐system level. The methodology asks the evaluator to select what changes he/she is seeing in the specific new invention versus the prior art. Based on the selected change – the method gives a change score (CS) to the specific change and invention score (IS) to the specific change that has been implemented. For example, if at subsystem level a component has been removed (trimming in TRIZ parlance) in the invention it is given higher invention score than say if the component has been changed. Further the 39 parameters identified by classical TRIZ – the contradiction matrix are divided into three categories – physical parameters, performance parameters and finally ability parameters. The evaluator is asked to select if there are any improvements that he/she sees in these parameters at the system level Compared to Prior Art T H I S Changes at subsystem levels N o Component Changed Component Removed Component Added Subsystem interface changed Changes at system levels N o Subsystem Changed Substantially Subsystem Removed Subsystem Added Subsystems merged Subsystem divided New subsystem interface created Changes at Supersystem levels N o System Removed Function Remains Systems Merged System Interface Changed New System Interfaces Created Potential changes and subsystem level respectively. Once again the tool gives specific scores to the change (the change score) and the invention score (IS) based on specific changes observed. Finally the tool asks the evaluator if there are any technical or physical contradictions resolved in the current invention over prior art. Based on the number of technical and/or physical contradictions resolved in the invention, the tool assign a change score and invention score to the invention on the TC and PC parameter as well. Finally we sum over all the invention scores weighted by the change score, i.e. Relative Invention Score