On June 18, Howard Marks, co-founder of Oaktree Capital, discussed whether the current market is experiencing 'irrational exuberance' and the opportunities and risks under the AI investment boom in a recent podcast. He noted that the current market can be described using Alan Greenspan's words from 30 years ago; we are in a 'boom,' but no one can definitively say whether it is 'irrational.' Using SpaceX's impending IPO with a valuation of nearly $2 trillion as an example, he stated that deciding whether to participate and at what price is purely a matter of 'guessing,' and cannot be calculated like traditional value investing. Howard mentioned his favorite saying: 'Cautious individuals struggle to achieve great things.' He pointed out a current investment dilemma: investing in tech giants may lead to significant mistakes, but it can also yield remarkable successes. Those who hesitate out of fear of risk may miss out on the greatest investment opportunity in human history. In contrast, investors in traditional industries such as transportation, retail distribution, and real estate are unlikely to make catastrophic investment errors, but they also cannot seize the monumental benefits of this transformative era. In terms of valuation, Howard provided a key reference: the current price-to-earnings ratio of the S&P 500 is about 23 times, which is approximately 50% higher than the 80-year average of 16 times, but far lower than the 32 times during the 2000 internet bubble and below the 60 to 90 times level of the 'Nifty Fifty' era, indicating that overall it is 'high but not out of control.' Regarding AI investments, he proposed a three-tiered investment strategy: investing in large-scale tech companies is a low-risk approach due to their established business and cash flow; investing in vertical AI companies like Anthropic and OpenAI carries higher risks but also a higher probability of survival; while investing in early-stage startups is akin to gambling, where most will lose everything, but a few will become extremely wealthy. He advised investors to choose where they want to invest on the risk spectrum, mix different positions along the spectrum, and then determine what proportion these companies should represent in their overall investment portfolio.