While searching on the Web about the Synod of Dort, I have found this post on Heidelblog. It takes a long time preparing the ground to defend that the Arminianism is mere repackaged Pelagianism:
Did Synod condemn the Remonstrants as heretics? If we consider the various points at which Synod flatly characterized the errors of the Remonstrants as heresy, the ways in which Synod repeatedly associated the Remonstrants themselves with the Pelagians, and characterized their errors as Pelagian it seems hard to avoid the conclusion that, for the Synod of Dort, the revisions proposed by the Remonstrants were errors of such a magnitude that they not mere errors and not merely heresy in the broad sense, but heresy in the narrow, technical sense described in the first part of this essay: an error transgressing the ecumenical teaching of the church as agreed at Ephesus in 431, in the condemnation of Coelestius (and through him, Pelagius).
The article concludes with an emphatic:
... Synod did not invoke the category of heresy lightly or unintelligently. They knew what they were doing and they used that language advisedly. It was meant to be bracing to the churches and to her ministers and so it should once again have that same affect in us.
It is a bit strange to me hearing this, because many modern confessional Calvinists regularly recognize that the teachings of Arminius and Wesley about the condition of fallen human race (a.k.a. Total Depravity in the TULIP lingo) were orthodox.
From memory I remember Sproul finds no fault on Arminius about this specific subject, saying that his descriptions are as strong as any Reformed preacher like Calvin or Luther himself.
Charles Spurgeon aggrees with and praises John Wesley on his book The Two Wesleys, and he also quotes Arminius "verbatim-translated":
With the exception of ancient Pelagians and their modern off-spring, I do not know that the Church has afforded any instance of any professors who have doubted the inability of man apart from God the Holy Spirit. Our confessions of faith are nearly unanimous upon this point. But I hear someone say—"Do not the Arminians believe that there is natural strength in man by which he can do something?" No, my Brothers and Sisters, the true Arminian can believe no such thing! Arminius speaks right well upon this point. I quote his words, as I have them in a translation
It is impossible for free will, without Grace, to begin or perfect any true or spiritual good. I say, the Grace of Christ, which pertains to regeneration is simply and absolutely necessary for the illumination of the mind, the ordering of the affections, and the inclination of the will to that which is good. It is that which operates on the mind, the affections, and the will, which infuses good thoughts into the mind, inspires good desires into the affections, and leads the will to execute good thoughts and good desires. It goes before, accompanies, and follows; it excites, assists, works in us to will, and works with us that we may not will in vain. It averts temptations, stands by and aids us in temptations, supports us against the flesh, the world, and Satan; and in the conflict, it grants us to enjoy the victory. It raises up again those who are conquered and fallen; it establishes them and endues them with new strength, and renders them more cautious. It begins, promotes, perfects and consummates salvation. I confess that the mind of the natural and carnal man is darkened, his affections are depraved, his will is refractory, and that the man is dead in sin.
That being said, is it true to say that every Calvinistic confession that adheres to Dort automatically/logically implies Arminianism is a repackaging of heretic Pelagianism?