To learn modern mathematics, it's essential to first establish a solid foundation in traditional subjects such as algebra, trigonometry, calculus, and linear algebra. While calculus and discrete mathematics may be considered "ancient," they remain relevant and are prerequisites for more advanced topics. The discussion emphasizes that modern mathematics doesn't necessarily refer to concepts developed in the last century, as many foundational theories are still valid and useful today. Resources like MIT OpenCourseware can provide structured learning paths, and engaging with subjects like functional analysis, abstract algebra, and differential geometry can lead to a deeper understanding of contemporary mathematics. The conversation highlights that the age of mathematical theories is less important than the knowledge and skills required to tackle more advanced topics. Ultimately, personal interest should guide the choice of subjects to study, as enjoyment can enhance the learning experience.