When readers see emphasis in a quotation, they don't know whether it was already there or was added by the quoter. Here's how to handle these cases:
Locke argues that every individual in the state of nature has a right to enforce the laws of nature: "the execution of the law of nature is, in that state, put into every man's hands . . ." （9, emphasis in the original）.
For Wollstonecraft, universal education is critical: "my main argument is built on this simple principle, that if she [woman] be not prepared by education to become the companion of man, she will stop the progress of knowledge and virtue; for truth must be common to all, or it will be inefficacious with respect to its influence on general practice" （86, emphasis added）.
Locke argues that every individual in the state of nature has a right to enforce the laws of nature: "the execution of the law of nature is, in that state, put into every man's hands . . ." （9, emphasis in the original）.
For Wollstonecraft, universal education is critical: "my main argument is built on this simple principle, that if she [woman] be not prepared by education to become the companion of man, she will stop the progress of knowledge and virtue; for truth must be common to all, or it will be inefficacious with respect to its influence on general practice" （86, emphasis added）.