We explored the features and traits of the researchers behind history's biggest breakthroughs, enabling us to build a general profile of who science's greatest discoverers are and the basic environment they work in. These pioneering researchers have been D evolving, shifting towards greater interdisciplinary education and method training, and they are not as young as before, but still overall young. One background trait stands out remarkably among the rest: about half of all discoveries are made by scientists with at least two degrees in different fields. This underscores a critical insight. Researchers trained across disciplines and methods are more likely to make new method connections across fields, sparking breakthroughs at the intersection of fields. Not only interdisciplinary but also early career researchers are central in the process. We found that the golden age of innovation in science falls between 35 and 45— with very few major breakthroughs occurring after 50 and almost none after 60. For younger, more motivated researchers generally bring more recent training in cuttingedge tools and fresh perspectives. Science, at its core, needs to reward those willing to take risks and challenge the status quo. Strikingly, scientific progress is not confined to elite institutions—with seven in ten discoverers not at top-tier universities. Groundbreaking research can emerge anywhere, as long as researchers have the right tools and the basic conditions (basic facilities and resources) and freedom to do research. So what do we learn by exploring the background traits of discoverers? There are critical opportunities here: we could achieve more breakthroughs if research institutions and agencies better incentivise researchers to push beyond the common trend of narrow specialisation. By fostering interdisciplinary innovation that blends novel methods across fields, we open up entirely new ways to tackle problems and spark innovative solutions. These unexpected solutions would not have been possible in a single discipline—from MRI and the gene-editing method CRISPR to AI methods. It is crucial for us to break down the artificial boundaries between fields to enable researchers to explore connections they could otherwise not make. To unlock untapped areas of innovation, we need to remove disciplinary barriers to sharing powerful tools across fields and prioritise developing new integrated tools. Also providing incentives for underrepresented groups—including female researchers—is important to ensure a more inclusive scientific community that taps into the full range of human potential and fosters discovery. Here we traced the evolution of science's greatest discoverers and the scientific system they do research in. We later dig deeper into how the tools these discoverers used are commonly the central driver in powering our biggest breakthroughs (Chapter 6). But before that, we explore in the next chapter how innovations in tools also trigger new scientific fields—not just discoveries. By understanding the methods-and toolspowered nature of science, and how we can accelerate it, we set the stage for more strategic and rapid scientific progress.