There's a lot of completely intractable problems rolled up into this. The most obvious one is that there's no objective formal definition of "good" that you can

There's a lot of completely intractable problems rolled up into this. The most obvious one is that there's no objective formal definition of "good" that you can use to reliably rank your different options by goodness. Given an amount of donated money, how many people would it need to lift out of poverty before that option is better than saving one life? Does the number change based on the situations of the people involved? Is saving the life of an old woman as "good" as saving the life of a child? What if the child is unhealthy or in a very dangerous environment, and your "saving" of their life only gives them the opportunity to die of something else three months down the line? Out of all possible options, finding the one that does the most good is akin to solving infinite trolly problems. But let's say you somehow do that, and you find (for example) that investing in education always gives you the best marginal return on goodness per dollar. Now we have an interesting optimization problem that depends on a lot of factors. For starters, we always have the option of taking some of our available time and using it to grow our money before allocating it to philanthropy. Will you do more good donating $1B to education over 30 years than you would spending 10 years doubling the money with investments and then donating $2B to education over the next 20 years? $4B over 10 years? $8B all at once, 30 years from now? For effects that snowball, do we care about goodness accumulated after your 30 year cutoff, or is that just the limit in which we have to spend the money before sitting back and counting up the change in goodness for the rest of time? If we stop looking at the future after the 30 year cutoff, you'll end up choosing options that maximize short term goodness but are completely dwarfed in the long term by other options. If we do consider the future after the cutoff, then the best option almost always degenerates to some form of "use the money to continually amass more money and power until you have so much power that you control everything, and then unilaterally force humanity to do as much good as possible" which pretty much just turns you into a supervillain (again, "good" is relative). You will also need to deal with diminishing returns and potential value drift on top of your already impossible optimization problem, so have fun with all that too. Of course, your more immediate hurdles are going to be administrative. Assuming you've found a pretty good cause to devote your money to, how do you stop that money from being used inefficiently? Greedy people are going to try and siphon money for themselves out of your philanthropy, and stupid people are going to waste some portion of your money that they control even if they have good intentions. How much of your money is it worth spending on hardening the rest of your money from misuse?