How "scientists" protect themselves

The word "scientist," like the word "engineer," has depreciated a lot, like currencies in third-world countries.  "Cognitive scientists," "Neuro scientists," "Social scientists" and more. Most of these new scientists deal with conjectures, theories, speculation, guesses... but they protect themselves. Two examples:

Steven Pinker, Harvard University,  says, in his "How the Mind Works", at the very start of the book: "... we don´t know how the mind works..."  and then he proceeds to write 660 pages. Suck on that! 

Paul Bloom, from MIT, tenders, in the final chapter of his "How Children Learn the Meaning of Words," a revealing confession: "Nobody knows how children learn the meaning of words."

Do not forget to add a caveat like the two above, when writing a "scientific" paper, just in case.