Quantitative way of thinking is very critical in today’s day and age. For example, if we say an industry has high returns on equity, it is technically a meaningless statement. We should dig deeper. How do we define high? Is high to be defined in absolute terms or relative terms. If relative, relative to what and for how long? The moment you start making an effort to quantify things, you will see a lot more clarity. You will need to spell out your assumptions. There is no place to hide behind vague terminology.
There is a lot of discussion on the market being in bubble territory. Again, we should stop ourselves and ask, what is a bubble? How do we quantify a bubble? There are a lot of academic papers on quantifying bubbles but suffice it to say that there is no universal definition or quantifying methodology of a bubble. So, we should try and define what we would think a bubble would be in our own terms. A bubble is when a particular asset price goes up significantly over a short period of time without the underlying cashflow (if any) of the asset changing meaningfully.
So, from a stock market perspective, we could think of a finding out how many stocks are trading say 2x-3x above their 200-day moving average. Another similar approach could be to look at the number of stocks that are above 3 standard deviations of their 200-day moving average. Couple that with a valuation metric like say 3 times PE or PEG or EV/EBIDTA over their mean for 3-5 years. And voila, you have a framework to understand what a bubble looks like. It may not be perfect, but you can keep refining it over time. But your understanding of markets will increase significantly more than listening to random people bandying such terms all over the place.