IAs require varying amounts of time and effort. This implies a trade-off: less time, effort, or resources will be left over for focusing on LCs. Might this mean less income? No new car this year? It just might. But let’s review Premise One: where an activity (all things considered) increases your well-being then your interest is to do it.
So the proper standard, when deciding where to invest your time and effort, should be: which will yield me a greater marginal boost in well-being: investing my resources in LCs or in IAs?
Well, we’ve already shown the diminishing correlation between income and happiness, and the futility of buying happiness through material possessions. Yes, time and effort diverted from LCs towards IAs may result in minor backsliding on LCs. Or maybe it won't (more on this later). What it will do, with scientific certainty, is significantly boost well-being. You might not get that promotion, but you’ll be happier than you would have been if you had. Because science.
Not only that, most of us aren’t 100% occupied all the time on work that directly affects our LCs. So, with a little discipline, we can find time for IAs when we’d otherwise be unproductive (you know, Candy Crush and Pinterest). If you’re focused on this as a trade-off, though, keep the Individual Premise in mind: maximizing your well-being is the point. LCs and IAs exist to serve this goal. So if a better blend between IAs and LCs means slightly lower income or a less flashy watch, you’re still #winning because, you know, happiness.