The S&P 500 is up 13% this year despite inflation and geopolitical issues. Valuations are getting high, with the Shiller CAPE ratio nearing the peak we saw during the 2000 dot-com bubble. The current situation with AI is looking a lot like the early internet days. Tech companies are spending massive amounts on AI infrastructure, similar to the fiber-optic buildout back then. The Magnificent Seven companies are starting to burn through free cash flow and take on debt to fund this AI push. While the broader economy still looks okay with low unemployment, the high valuations in AI stocks are a warning sign. If you're investing long-term, it might be safer to stick with companies trading at reasonable valuations that can handle a potential AI pullback. Stocks like Microsoft, Alphabet, Amazon, and Apple fit this category, with Apple being the least exposed to the massive AI infrastructure spending.