Ho provato a fare così ma non funziona

codice:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.Threading;


namespace copiaWebService
{
    
    public partial class Form1 : Form
    {

        copiaDati cp = new copiaDati();
    
        public Form1()
        {
            InitializeComponent();
        }
...
...
        private void startButton_Click(object sender, EventArgs e)
        {

            Thread t = new Thread(new ThreadStart(cp.scriviStato(cp.Copia(this.textBox1.Text,this.textBox2.Text))));
            t.Start();
      

           

        }
...
...
public class copiaDati
    {
        String okMessage = "FATTO!";
        String errMessage = "File origine non aggiornato";

        public String Copia(String fileNameSrc, String fileNameDst)
        {
            DateTime dataFileSrc = File.GetLastWriteTime(fileNameSrc);
            DateTime dataFileDst = File.GetLastWriteTime(fileNameDst);
            if (dataFileSrc > dataFileDst)
            {
                if (File.Exists(fileNameDst + ".old"))
                    try
                    {
                        File.SetAttributes(@fileNameDst + ".old", FileAttributes.Normal);
                        File.Delete(fileNameDst + ".old");
                    }
                    catch (Exception e)
                    {
                        MessageBox.Show(e.ToString());
                        return "";
                    }
                else
                    File.Copy(fileNameDst, fileNameDst + ".old");

                if (File.Exists(fileNameDst))
                    try
                    {
                        File.SetAttributes(@fileNameDst, FileAttributes.Normal);
                        File.Delete(fileNameDst);
                    }
                    catch (Exception e)
                    {
                        MessageBox.Show(e.ToString());
                        return "";
                    }

                File.Copy(fileNameSrc, fileNameDst);
                return okMessage;
            }
            return errMessage;
        }

        public String scriviStato(String res)
        {
            String s = null; ;
            s = DateTime.Now.ToString();
            if (res == okMessage)
                s += " --> " + okMessage;
            else
                s += " --> " + errMessage;
            s += "\n";

            return s;
        }
    }
Quando compilo mi da un errore su:
Thread t = new Thread(new ThreadStart(cp.scriviStato(cp.Copia(this.textBox1. Text,this.textBox2.Text))));

dicendo: "è previsto il nome di un metodo".
Come mai?